1. Field of the Invention
The invention relates to an antenna unit, and particularly to an antenna unit capable of operating at various wireless communication bands.
2. The Related Art
Recently, a portable electrical device is required to be compact, light, and multi-functional according to a recent demand. Electrical circuits and components built in the mobile communication terminal become smaller and more multi-functional in order to satisfy the above requirement. Also, the requirement is applied to an antenna, which is one of major components of the portable electrical device for wireless communication purpose.
Wireless communication bands include global system for mobile communications (GSM) frequency band about 850 mega-hertz (MHz), extended global system for mobile communications (EGSM) frequency band about 900 MHz, digital cellular system (DCS) frequency band about 1800 MHz, personal conferencing specification (PCS) frequency band about 1900 MHz, wideband code division multiple access (W-CDMA) frequency band about 2100 MHz and wireless fidelity (Wi-Fi) frequency band having 2.4 giga-hertz (GHz) and 5.2 GHz nowadays. Therefore, an antenna capable of operating in various wireless communication bands being mentioned above is a necessary component for the portable electrical device.